Method for manufacturing a wind turbine rotor blade

ABSTRACT

A method for forming a profile for a hollow component is provided. A first composite fibre layer is laid out on a first surface corresponding to a first profile section of the component. A second composite fibre layer is laid out in a second surface corresponding to a second profile section of the component. A collapsed bag is laid out in onto the first composite fibre layer. The bag and the first composite fibre layer are fixed to the first surface. First and second mould elements are coupled such that the first surface and the second surface correspond to the first and second profiles. The bag is inflated such that the first composite fibre layer is pressed to the first surface and the second composite fibre layer is pressed to the second surface so that the first and second layers are coupled to form the profile.

FIELD OF INVENTION

The present invention relates to a method for forming a profile formanufacturing a hollow component made of composite fibre, in particularof a hollow blade for a wind turbine. Moreover, the present inventionrelates to a blade for a wind turbine and to a moulding system.

ART BACKGROUND

Wind turbine blades for wind turbine becoming larger and larger in size.Hence, modern wind turbine blades are mostly made of composite fibre, inparticular made of glass fibre. In order to manufacture such large windturbine blades, several manufacturing methods, such as resin transfermoulding, are applied.

EP 1 310 351 A1 discloses a method for manufacturing blades for a windturbine. A mould core is placed to a layer of glass fibre, which is laidin a mould part forming an underside of a blade. On top of the mouldcore, a further layer of glass fibre is laid. Finally, an upper mouldpart is laid over the mould core, so that the fibre layers that arepressed to the mould core form the profile of the blade.

After curing of the fibre layers in the mould parts, the mould core hasto be removed, which may cause difficulties due to the large size of thewind turbine blades and due to the complex profiles of the wind turbineblades.

SUMMARY OF THE INVENTION

It may be an object of the present invention to simplify a manufacturingmethod for a wind turbine blade.

This object is solved by a method for forming a profile formanufacturing hollow components made of composite fibre, in particular ahollow blade for a wind turbine, by a blade for a wind turbine and by amoulding system for applying the method according to the independentclaims.

According to a first aspect of the present invention, a method forforming a profile for manufacturing a hollow component made of compositefibre, in particular a hollow blade for a wind turbine, is presented.According to the method, a first composite fibre layer is laid out on afirst mould surface of the first mould element, wherein the first mouldsurface corresponds to a first profile section of the hollow componentto be manufactured. A second composite fibre layer is laid out in asecond mould surface of the second elements, wherein the second mouldsurface corresponds to a second profile section of the hollow componentto be manufactured. A bag is laid out in a collapsed state onto thefirst composite fibre layer.

The bag and the first composite fibre layer are fixed to the first mouldsurface. The first mould element is coupled to the second mould elementin such a way, that the first mould surface and the second mould surfacecorrespond to the profile of the hollow component (e.g. the wind turbineblade) to be manufactured. The bag is inflated in such a way, that thefirst composite fibre layer is pressed to the first mould surface andthe second composite fibre layer is pressed to the second mould surface,so that the first composite fibre layer and the second composite fibrelayer are coupled to form the profile of the hollow component to bemanufactured.

According to a further exemplary embodiment, a blade for a wind turbineis presented, wherein the blade is manufactured by the above mentionedmethod.

Moreover, according to a further aspect of the present invention, amoulding system for applying the above mentioned method for themanufacturing hollow components made of composite fibre is presented.

The first mould element may be an upper mould part and the second mouldelement may be a lower mould part of a moulding device. The first mouldelement may comprise the first mould surface, wherein the first mouldsurface forms for example a female mould of a first section of a profileof the hollow component to be formed. When laying a first compositefibre layer into the first mould element on the first mould surface, thefirst composite fibre forms the first profile section of the hollowcomponent. For example, if the first mould element is an upper half andthe second mould element is a lower half, the first mould surface formsa female mould of the upper half of the hollow component (e.g. upperhalf of a blade) to be manufactured and the second mould surface forms afemale mould of the lower half of the component (lower half of theblade) to be manufactured. Beside this, the moulding device may comprisethe first mould element, the second mould element and further moldelements, so that the mould surface is formed by the first mouldsurface, the second mould surface and the further mould surface, towhich two or a plurality of individual composite fibre layers may belaid onto. In other words, the final profile of the component tomanufactures may be divided in more than two profile sections.

The composite fibre layers may be formed with fibres in auni-directional or multi-directional orientation with respect to eachother. Moreover, the composite fibres may be provided in a web form, awoven form, such as a fibre mat or a prepreg. The first fibre layer maydescribe one or a plurality of fibre layers laid on top of each otherlocated to the first mould element and the second fibre layer describesone or a plurality of fibre layers laid on top of each other located tothe second mould element.

The composite fibres may comprise glass fibres, carbon fibres or otherpolymer fibre materials.

The bag is a flexible, i.e. inflatable and foldable, hollow body madefor example of rubber or other elastic material.

The bag may be collapsible and inflatable. In a collapsed state, the bagis folded and minimized in size and in the inflated state, the bag ismaximized in size. The inflatable state of the bag may be achieved byblowing-in pressurized air inside the hollow bag or by applyingunderpressure at the environment of the bag. The bag is impermeable withrespect to e.g. liquids i.e. resin and airtight.

By the present invention a mould dorn to which composite fibre layersare placed in the prior art manufacturing methods may be obsolete and ahollow component, such as the blade of wind turbine, may be manufacturedin one step. This is achieved by fixing (securing) the collapsed bag andthe first composite fibre layer to the first mould element. The fixingof the bag and the first composite fibre layer may be achieved byapplying an adhesive (e.g. resin) or by providing underpressure betweenthe bag and the first mould surface. Hence, when the bag and the firstcomposite fibre layer is fixed to the mould surface, the first mouldelement may be handled very simple and no slipping and relative movementof the first composite fibre layer with respect to the first mouldsurface is caused, because the first composite fibre layer is pressed onthe first mould surface by the bag. For this reason, the first mouldelement may be turned overhead without a falling-out of the bag and thefirst composite fibre layer out of the first mould element. Hence, thefirst mould element and the second mould element may be assembled easilyand later after a coupling of both mould elements, finalizing steps,such as resin injection or curing may be applied for finalizing theprofile of the component to be formed.

By the prior art manufacturing methods, a massive dorn is put to acomposite fibre layer in a mould element and later the second compositefibre layer has to be placed on top of the massive dorn. Finally, thesecond mould element is coupled to the first mould element, whereinthere is a risk that the second composite fibre layer slips away.Moreover, the adjustment of all parts in the mould element is complex.With the presented inventive method, the first composite fibre layer andthe inflatable bag are already fixed and aligned to the first mouldelement before the first mould element is coupled to the second mouldelement. For this reason, a slipping of the first composite fibre layerwith respect to the first mould element may be prevented. A pressing ofthe composite fibre layers to the surfaces of the mould elements may beaccomplished by the inflatable bag. For the fixing of the bag and thefirst composite layer to the upper first mould element, a massive dornmay be obsolete.

Additionally, after curing the composite fibre layers, the bag may becollapsed and thus reduced in size again, so that the bag may easily beremoved from the inner cavity of the manufactured hollow component.

This is beneficial, if a complex component, such as a blade for a windturbine, is manufactured that is e.g. twisted in its length direction.By such a twisting of the wind turbine blade, conventional massive dornsare complex to remove. By the inflatable bag, an easy removal of the bagfrom the inner cavity of a finalized wind turbine blade is achieved.

According to a further exemplary embodiment of the present invention,the fixing of the bag is achieved by sucking off air between the bag andthe first mould surface, such that the bag and the first composite fibrelayer are fixed to the first mould surface by underpressure (i.e.vacuum). Hence, by the present exemplary embodiment the bag may easilybe removed when stopping to suck-off air. Additionally or alternatively,the bag and/or the first composite layer may be fixed to the first mouldsurface by an adhesive (e.g. resin), for example. An additional fixingpressure from outside, e.g. by a massive dorn, may be obsolete.

According to a further exemplary embodiment, the first composite layeris larger than the first mould surface such that the first compositefibre layer forms a surplus section that extends over an edge of thefirst mould surface. The surplus section describes an excess length, anoverhang or a protrusion. By using a surplus section in particular atthe margin areas of the first composite fibre layer, an overlapping ofthe second composite fibre layer over the edges of the mould element,which edges defines the area of the first mould surface corresponds to asize of a respective profile section, may be achieved. The surplussection is movable (e.g. foldable) and is not fixed to the first mouldsurface by the bag.

According to a further exemplary embodiment, the coupling of the firstmould element to the second mould element comprises an adjusting of thefirst mould element to the second mould element in such a way, that thesurplus section overlaps partially with the second composite fibre layerin the second mould element. Hence, the contact areas (interfacesections) between the first composite fibre layer and the secondcomposite fibre layer may be reinforced, so that a more robust componentmay be manufactured. Thereby, during the adjustment of the first mouldelements to the second mould elements, the surplus section is bended tothe inside into a cavity formed between the coupled mould elements, sothat the surplus section overlaps with the second composite fibre layer.

In another exemplary embodiment of the present invention, the adjustingcomprises an arranging of the first mould element in such a way that thesurplus section is aligned in a predetermined position by gravity. Next,the first mould element is brought together with the second mouldelement, wherein, when the surplus section is in the predeterminedposition, the surplus section overlaps partially with the secondcomposite fibre layer in the second mould element. For example, if thefirst mould element is turned overhead, the surplus section, which isnot fixed to the first mould element, is aligned in a proximatelyvertical orientation, because of gravity. When bringing together thefirst mould element and the second mould element, the end of the surplussection touches the second composite fibre layer. When moving the firstmould element and the second mould element further together, the end ofthe surplus sections slides along the sec- and composite fibre layer inthe direction to the inner cavity formed between the first mould elementand the second mould element. Hence, in a final state, when the firstmould element and the second mould element are fixed together finally,the surplus section forms the overlap section with the second compositefibre layer.

According to a further exemplary embodiment, the inflating of the bagcomprises a lifting of the surplus section by inflating the bag in sucha way that the surplus section overlaps partially with the secondcomposite fibre layer in the second mould element. By the presentexemplary embodiment, the surplus section may be folded in such a waythat the surplus section lies onto the collapsed surface of the bag. Theinflating of the bag causes the surplus section to move together withthe surfaces of the bag until the bag is inflated to its final position.In the final position, the surplus section is pressed on the secondcomposite fibre layer.

According to a further exemplary embodiment of the method, a secondcomposite fibre layer is larger than the second mould surface such thatthe second composite fibre layer forms a further surplus section, thatextends over an edge of the second mould surface. The coupling of thefirst mould element to the second mould element further comprises anadjusting of the first mould element to the second mould element in sucha way, that the further surplus section overlaps partially with thefirst composite fibre layer in the first mould element.

According to a further exemplary embodiment, the method comprises beforecoupling the first mould element to the second mould element a mountingof a web to the first composite fibre layer or to the second compositefibre layer in such a way that after coupling of the first mould elementwith the second mould element the web is coupled with the firstcomposite fibre layer and the second composite fibre layer forreinforcing the hollow component to be manufactured.

The web describes a robust and hard element that consists of e.g. wood,metal, composite fibre materials or other hard and inelastic materials.The web is mounted inside the inner cavity of the hollow component to bemanufactured and is in contact with the first composite fibre layer andthe second composite fibre layers, so that a force may be transmittedbetween the layers. Hence, a reinforcement of the composite fibrecomponent is generated.

The web may be fixed to the first composite fibre layer, e.g. by weldingor gluing. Moreover, the web may be wrapped into the composite fibrematerial of the first and/or second composite fibre layer.

According to a further exemplary embodiment, the method comprises beforecoupling the first mould element to the second mould element a mountingof a web to the first composite fibre layer and a mounting of a web tothe second composite fibre layer in such a way that after coupling ofthe first mould element to the second mould element the web and thefurther web are coupled with each other for reinforcing the hollowcomponent to be manufactured. The web and the further web each comprisesfor example a first face to which the web and the further web aremounted to the respective composite fibre layer. The web and the furtherweb each may comprise a further face, with which the webs contact eachother. Hence, a force may be transmitted between the web and the furtherweb and hence, a force may be transmitted between the composite fibrelayers for reinforcing the hollow component to be manufactured.

According to a further exemplary embodiment, the inflating of the bagcomprises a sucking off air between a) the bag and the first mouldsurface, and b) the bag and the second mould surface. Hence, the bagpresses the first composite fibre layer to the first mould surface andthe second composite fibre layer to the second mould surface. The bagmay comprise in its inflated state a shape of the profile of thecomponent to be manufactured. Alternatively, the bag may be elastic, sothat the bag may comprise an arbitrary shape and the inflated shape ofthe inflated elastic bag adjusts itself by sucking off air or byblowing-up the bag until the final profile of the component to bemanufactured is achieved and the shape of the (elastic) bag adjustsitself to the shape of the first mould surface and the second mouldsurface.

The first mould element and/or the second mould element may compriseconnections, to which a vacuum pump may be connected for sucking off airfrom the respective mould surfaces. Hence, e.g. a sucking off of the airbetween the bag and the first mould surface leads to an inflating of thebag. In other words, the inflating of the bag may be achieved by apressure difference between the inside of the bag and the outside of thebag.

According to a further exemplary embodiment, the inflating of the bagcomprises a blowing-in pressurized air into the bag, such that the bagpresses the first composite fibre layer to this first mould surface andthe second composite fibre layer to the second mould surface. Hence, thepressure difference between the inside of the bag and the outside of thebag is achieved by blowing-in pressurized air.

According to a further exemplary embodiment of the present invention, amoulding system for applying the above described method formanufacturing a hollow component made of composite fibre is presented.The moulding system comprises the first mould element, the second mouldelement and the bag.

By the present invention, a manufacturing method is presented, wherein acomponent, e.g. a hollow turbine blade, may be manufactured in onesingle mould process and wherein a massive dorn inside the hollowcomponent for manufacturing purposes may be obsolete.

In a first step, composite fibre layers, such as glass fibre layers,that form the blade are laid out into two separate mould elements,wherein each first and second mould element may form approximately ahalf-profile of the blade. For example, the profile of the wind turbineblade may be divided by the main camber line (main line) that connectsthe leading edge of the turbine blade to the trailing edge of theturbine blade, so that the first mould element comprise a mould surfacethat corresponds to the upper half of the turbine blade profile, and thesecond mould surface of the second mould element corresponds to thelower half of the turbine blade, for example.

The glass fibre layers are laid in the respective mould elements foreach blade half, respectively. To the blade halves, one or more bladewebs made be attached, e.g. by wrapping the webs into the glass fibrematerial, in order to ensure a secure fastening of the web to the restof the blade structure.

Moreover, a surplus glass fibre material, which extends over a side ofone of the mould surfaces, may be provided.

In a second step of the method, one or more air and resintight bags arelaid over substantially the entire mould surface of the composite fibrelayer in particular to the first mould element, which e.g. comprisesalso the surplus section of the glass fibre material.

The bag covers at least a major part of the first composite fibre layer.In particular, the bag does not cover the surplus section of the firstcomposite fibre layer, so that the surplus section is still movable.

The bag surface or the sum of the surface of the plurality of bagsshould have a surface size, which is at least twice the area, which isin contact with the first composite fibre layer, so that afterinflating, the bag also covers a corresponding section of the secondcomposite fibre layer.

In a third step, in particular a vacuum is applied in the space betweenthe first mould surface and the bag. By applying a vacuum(underpressure) in the space, the bag is dragged towards the first mouldsurface and presses the first composite fibre layer to the first mouldsurface. This in turn holds the first composite fibre layer and the bagfixed in position in the first mould, even if the bag does notcompletely cover the whole surface area of the first composite fibrelayer.

In a fourth step, the first mould element is rotated overhead, e.g. 180degrees around a longitudinal axis of the first mould element, to anup-side-down position of the first mould element, including the bag, thefirst composite fibre layer and the, for example. Hereby, thefree-movable surplus section hangs down from the first mould element inan approximately vertical direction caused by gravity.

In a fifth step, the first mould element is lowered and positioned withrespect to the second mould element. The surplus section is herebyfolded into the cavity that is formed between the first mould elementand the second mould element and the surplus section is aligned with theinner surface of the second composite fibre material in the secondmould.

In a sixth step, the bag is unfolded and inflated in order to fill theentire inner cavity between the first mould element and the second mouldelement, respectively between the first composite fibre layer and thesecond composite fibre layer. Thereby, the bag holds the composite fibrelayers to the respective mould surfaces.

The unfolding of the bag may be performed by either applying anunderpressure (vacuum) to the cavity, in particular between the surfaceof the bag and the first mould surface and the second mould surface.Moreover, the bag may be inflated by pressurized air that is blowninside the bag.

In order to provide an airtight connection between the first mouldelement and the second mould element and in order to achieve an airtightinner cavity, seals may be interposed between the intersections betweenthe first mould element and the second mould element.

When the bag is unfolded and inflated, an underpressure (vacuum) may beapplied to the space between the first mould surface, the second mouldsurface and the bag, so that by resin injection, resin is injected tothe first composite fibre layer and the second composite fibre layer.Finally, curing and casting of the hollow components may be accomplishedand the finished hollow component may be removed easily from the mouldelements.

The surplus section may be lifted to its final position to e.g. byinflating and unfolding the bag. The surplus fibre section may as wellbe formed at both composite fibre layers. If the hollow component is ablade of a wind turbine, the surplus section may be formed, e.g. in thefirst and/or the second composite fibre layer on e.g. the leading edgeof the blade or the trailing edge of the blade to be formed.

It has to be noted that embodiments of the invention have been describedwith reference to different subject matters. In particular, someembodiments have been described with reference to apparatus type claimswhereas other embodiments have been described with reference to methodtype claims. However, a person skilled in the art will gather from theabove and the following description that, unless other notified, inaddition to any combination of features belonging to one type of subjectmatter also any combination between features relating to differentsubject matters, in particular between features of the apparatus typeclaims and features of the method type claims is considered as to bedisclosed with this application.

BRIEF DESCRIPTION OF THE DRAWINGS

The aspects defined above and further aspects of the present inventionare apparent from the examples of embodiment to be described hereinafterand are explained with reference to the examples of embodiment. Theinvention will be described in more detail hereinafter with reference toexamples of embodiment but to which the invention is not limited.

FIG. 1 shows the first mould element and the second mould element in adecoupled state according to an exemplary embodiment of the presentinvention;

FIG. 2 shows the first mould element, to which the bag is placedaccording to an exemplary embodiment of the present invention;

FIG. 3 shows the first mould element, which is turned upside-downaccording to an exemplary embodiment of the invention;

FIG. 4 shows a coupling of the first mould element and the second mouldelement according to a further exemplary embodiment of the presentinvention; and

FIG. 5 shows a coupled state of the first mould element and the secondmould element according to an exemplary embodiment of the invention.

DETAILED DESCRIPTION

The illustrations in the drawings are schematical. It is noted that indifferent figures, similar or identical elements are provided with thesame reference signs.

In FIG. 1 to FIG. 5, a method for forming a profile for manufacturing ahollow component made of composite fibre, in particular a hollow bladefor a wind turbine, is shown.

FIG. 1 shows a first mould element 110 and a second mould element 120.To a first mould surface of the first mould element 110 a firstcomposite fibre layer 101 is laid out. The first mould surfacecorresponds to a first profile section of the hollow component to bemanufactured. For example, the hollow component is a blade of a windturbine, so that the first profile section may form a (upper) half ofthe blade to be manufactured.

A second composite fibre layer 102 may be laid out onto a second mouldsurface of the second mould element 120, wherein the second mouldsurface corresponds to a second profile section of the hollow componentto be manufactured. The second profile section may form a (lower) halfof the blade to be manufactured.

Moreover, as shown in FIG. 1, a web 105 may be attached to the firstmould element that is adapted for reinforce the hollow component to bemanufactured. To the first mould element 110 one or a plurality of webs105 may be attached and to the second mould element 120 one or aplurality of further webs 106 may be attached. The webs 105, 106 may beglued, welded or webbed to the respective composite fibre layers 101,102. The first and second mould surfaces are limited by respective edges104. As shown in FIG. 1, the first composite fibre layer 101 maycomprise surplus sections 103 that run over the edges 104 in a directionto outside of the respective mould surface. The surplus sections 103 areformed, when the first composite fibre layer 101 is made larger than thefirst profile section defined by the first mould surface, respectively.

FIG. 2 shows the first mould element 110 in a further method step. Tothe third composite fibre layer 101 a bag 201 is laid out, wherein thebag 201 is in a collapsed state. As shown in FIG. 2, it is also possibleto lay a plurality of collapsed bags 201 to the first composite fibrelayer 101. The surplus sections 103 are not covered by the bag 201, sothat the surplus sections 103 are freely movable. The web 105 may beadapted to be in contact with the surface of the second composite fibrelayer 102 or comprises a face that is in contact with a face of thefurther web 106 mounted to the second composite fibre layer 102. Theface of the web 105 or the further web 106 is not covered by arespective bag 201.

FIG. 3 shows a view of the first mould element 110 that is movedupside-down and in an overhead position. The freely movable surplussections 103 are aligned in general in a vertical position, for example,by gravity. The bags 201 and the first composite fibre layer 101 arefixed to the first mould surface of the first mould element 110. Thefixation may be generated e.g. by gluing (with resin) the elementstogether or by applying underpressure between the bag 201 and the firstmould surface. Hence, the bag 201, the web 105 and the first compositefibre layer 101 do not fall out of the first mould element 110 bygravity. Moreover a relative movement between the bag 201, the web 105and the first composite fibre layer 101 is prevented, so that noreadjustment later on is necessary.

FIG. 4 illustrates the first mould element 110 and the second mouldelement 120 in a state before the first mould element 110 and the secondmould element 120 contact each other. The surplus sections 103 areeither folded inwardly by additional devices. Moreover, the end faces ofthe surplus sections 103 may contact the second composite fibre section102, so that during movement of the first mould element 110 to thesecond mould element 120 the surplus sections 103 moves (slips)self-acting in a direction to the inner cavity formed between the firstmould element 110 and the second mould element 120.

FIG. 5 illustrates the first mould element 110 and the second mouldelement 120 that are in contact with each other. As shown in FIG. 5, thesurplus sections 103 of the first composite fibre layer 101 overlap thesecond composite fibre layer 102. In particular, the surplus sections103 overlap the second composite fibre layer 102 at a position, wherethe interface of the first mould element 110 and the second mouldelement 120 is located. In particular, if the first mould surface formsan upper half of a blade to be manufactured and the second mould surfaceforms a second half of the blade to be manufactured, the interface ofthe first mould element 110 and the second mould element 120 is built inthe region of the leading edge and the trailing edge of the blade to bemanufactured.

As shown in FIG. 5, in the coupled state of the first mould element 110and the second mould element 120, the web 105 and the further web 106are in contact with each other, so that a force may be transmitted fromthe first composite fibre layer 101 to the second composite fibre layer102. Hence, the web 105 and the further web 106 form a reinforcement ofthe hollow component to be manufactured. The inner cavity that is formedin the space between the first mould surface and the second mouldsurface, the bags 201 are inflated. Hence, the bags 201 press the firstcomposite fibre layer 101 and the second composite fibre layer 102 tothe respective mould surfaces. The inflating of the bag 201 may beachieved for example by injecting pressurized air inside of therespective bags 201. In another preferred embodiment, a vacuum pump maybe connected to the mould elements 110, 120, so that air is sucked-offfrom a space between the surface of the bag 201 and the first mouldsurface and the second mould surface (and the space between the bags 201and the respective web surfaces). Hence, by the pressure differencebetween the inner volume of the respective bag 201 and the outer spacebetween the bag 201 and the respective mould surfaces, the bags 201inflate and pressure the respective composite fibre layers to the mouldsurfaces. In order to optimize the sucking off of the air, sealingelements 501 may be attached to the interfaces between the first mouldelement 110 and the second mould element 120 in order to seal the innercavity formed inside the first mould element 110 and the second mouldelement 120.

Additionally, when an underpressure is generated between the bags 201and the first and second mould surfaces and the webs 105, 106, resin maybe injected, so that the composite fibre layers 101, 102 are soaked withresin.

Hence, after injecting the resin, the composite fibre layers 101, 102may be cured, so that the final profile and the final robust hollowcomponent, such as the blade, is manufactured. After curing of thecomposite fibre layers 101, 102, the underpressure between the bags 201and the first and second mould surfaces may be reduced, so that the bags201 collapse again. In the collapsed state of the bags 201, the bags 201comprise a reduced and small volume, so that they can be easily removedfrom the inner cavity of the manufactured component.

It should be noted that the term “comprising” does not exclude otherelements or steps and “a” or “an” does not exclude a plurality. Alsoelements described in association with different embodiments may becombined. It should also be noted that reference signs in the claimsshould not be construed as limiting the scope of the claims.

1-13. (canceled)
 14. A method for forming a profile for a hollow bladecomponent for a wind turbine, the method comprising: laying out a firstcomposite fibre layer on a first mould surface of a first mould element,wherein the first mould surface corresponds to a first profile sectionof the hollow blade component to be manufactured; laying out a secondcomposite fibre layer in a second mould surface of a second mouldelement, wherein the second mould surface corresponds to a secondprofile section of the hollow blade component to be manufactured; layingout a bag in a collapsed state onto the first composite fibre layer;fixing the bag and the first composite fibre layer to the first mouldsurface; coupling the first mould element to the second mould element insuch a way, that the first mould surface and the second mould surfacecorrespond to the profile of the hollow blade component to bemanufactured, and inflating the bag in such a way that the firstcomposite fibre layer is pressed to the first mould surface and thesecond composite fibre layer is pressed to the second mould surface, sothat the first composite fibre layer and the second composite fibrelayer are coupled to form the profile to be manufactured.
 15. The methodaccording to claim 14, wherein the fixing comprises sucking off airbetween the bag and the first mould surface such that the bag and thefirst composite fibre layer are fixed to the first mould surface byunderpressure.
 16. The method according to claim 14, wherein the firstcomposite fibre layer is larger than the first mould surface such thatthe first composite fibre layer faints a surplus section that extendsover an edge of the first mould surface.
 17. The method according toclaim 16, wherein the coupling of the first mould element to the secondmould element comprises adjusting the first mould element to the secondmould element in such a way that the surplus section overlaps partiallywith the second composite fibre layer in the second mould element. 18.The method according to claim 17, wherein the adjusting comprises:arranging the first mould element in such a way that the surplus sectionis aligned in a predetermined position by gravity, and bringing togetherthe first mould element with the second mould element, wherein, when thesurplus section is in the predetermined position, the surplus sectionoverlaps partially with the second composite fibre layer in the secondmould element.
 19. The method according to claim 16, wherein theinflating of the bag comprises lifting the surplus section by inflatingthe bag in such a way that the surplus section overlaps partially withthe second composite fibre layer in the second mould element.
 20. Themethod according to claim 16, wherein the second composite fibre layeris larger than the second mould surface such that the second compositefibre layer forms a further surplus section that extends over an edge ofthe second mould surface, and wherein the coupling of the first mouldelement to the second mould element further comprises adjusting thefirst mould element to the second mould element in such a way that thefurther surplus section overlaps partially with the first compositefibre layer in the first mould element.
 21. The method according toclaim 14, wherein before coupling the first mould element to the secondmould element the method further comprises mounting a web to the firstcomposite fibre layer or to the second first composite fibre layer insuch a way that after coupling of the first mould element to the secondmould element the web is coupled with the first composite fibre layerand the second composite fibre layer for reinforcing the hollow bladecomponent to be manufactured.
 22. The method according to claim 14,wherein before coupling the first mould element to the second mouldelement the method further comprises mounting a web to the firstcomposite fibre layer, and mounting a further web to the secondcomposite fibre layer in such a way that after coupling of the firstmould element to the second mould element the web and the further webare coupled with each other for reinforcing the hollow blade componentto be manufactured.
 23. The method according to claim 14, wherein theinflating of the bag comprises sucking off air between a) the bag andthe first mould surface, and b) the bag and the second mould surface,such that the bag presses the first composite fibre layer to the firstmould surface and the second composite fibre layer to the second mouldsurface.
 24. The method according to claim 14, wherein the inflating ofthe bag comprises blowing pressurized air into the bag such that the bagpresses the first composite fibre layer to the first mould surface andthe second composite fibre layer to the second mould surface.